Congress leaders have huddled together in recent days discussing post-poll alliances and sent feelers to smaller parties to prevent the BJP-led National Democratic Alliance from forming the next government.

Sonia, buoyed by the party's spectacular show in Andhra Pradesh, met Communist Party of India-Marxist General Secretary Harkishen Singh Surjeet -- who appears to have resumed the role of kingmaker after six years -- at his home to discuss political developments.

The talks focused on the possible shape and content of a coalition led by the Congress and supported by the Left parties and other secular parties.

Surjeet reportedly told Sonia that a Congress-led alliance would be a 'workable proposition' but with one rider -- former Union finance minister Dr Manmohan Singh be the prime ministerial candidate 'for the time being.'

Congress leaders too are coming around to discussing alternatives to Sonia.

Following its performance in Andhra Pradesh, Congress leaders say many regional parties have become more amenable to support a Congress-led government at the Centre.

"We are now certain that it is not going to be a BJP-led coalition government at the Centre but one of secular parties in which the Congress will be the main player," senior Congress leader Vayalar Ravi, who is credited with having inked the Congress-Nationalist Congress Party electoral alliance in Maharashtra, told rediff.com

Ravi flew from Kerala to Delhi on Tuesday following a summons from Sonia and plunged into talks with like-minded parties.

He parried a question on Sonia's foreign origins, saying the question of who would be the prime minister will be decided only after the Lok Sabha election results are out.

But the Congress fears that powerful players like Mulayam Singh Yadav and Sharad Pawar could either create problems for a Congress-led coalition or build bridges with the NDA if Sonia is projected as the prime minister.

A number of Congress leaders rediff.com spoke to on Tuesday said Singh might emerge as 'a consensus candidate' because leaders in like-minded parties are said to be 'receptive' to the idea.

Sonia is reportedly not averse to the idea but the question is what she will do in a coalition government led by Dr Singh, who as finance minister initiated India's economic reforms.

Various Congress leaders met with representatives of a number of smaller parties like the National Conference, Haryana Vikas Party, Asom Gana Parishad and Janata Dal (Secular) to enlist their support for a Congress-led coalition.

Sonia or her political advisers will meet with leaders of bigger regional parties like Samajwadi Party President Mulayam Singh Yadav, Bahujan Samaj Party chief Mayawati and NCP President Sharad Pawar on Wednesday to discuss the post-poll scenario.

"Every regional player would be willing to accept Dr Singh as prime minister. So, in our talks with the smaller parties, we have been told to hint that Dr Singh could be the prime minister," a Congress leader revealed.